The third explosion happened at around 11:50 a.m. in the 6700 block of Galindo Street, just off Montopolis Drive near the Hwy 183 and Hwy 71 intersection.

Austin Police Chief Brian Manley says a 75-year-old Hispanic woman was transported to a local hospital with critical, life-threatening, injuries. He said the victim found the package outside the home, and when she picked it up, it exploded.

Chief Manley said agents with the ATF, FBI, and the Postal Service are all assisting Austin Police with the investigation.

Everyone is being asked to not touch any packages that look suspicious -- call 911 immediately.

Texas Governor Greg Abbott says his office's criminal justice division is offering a reward of up to $15,000 for information leading to an arrest. Anyone with information can call the Texas Crime Stoppers hotline at 1-800-252-TIPS (8477) or text the letters "DPS" -- followed by your tip -- to 274637 (CRIMES).

EMS says a woman in her 70s was injured and is being transported to Dell Seton Medical Center with serious, potentially life-threatening injuries.